103 Minn. 224, 114 N.W. 1123 (Minn. 1908)
Anderson v. Minneapolis, St.
When a negligently set railroad fire merges with another fire of independent and possibly sufficient origin to destroy the plaintiff's property, must the plaintiff prove but-for causation, or is it sufficient to show that the railroad's fire was a material element and substantial factor in causing the loss, notwithstanding that the other fire might independently have caused the same destruction?
In cases of concurrent sufficient causes that combine to produce a single, indivisible harm, the plaintiff need not establish strict but-for causation. It is enough to show that the defendant's negligent conduct was a material element and a substantial factor in bringing about the harm. Where a defendant's negligence operates concurrently with another independent cause, the defendant remains liable unless it proves that the harm would have occurred in the same manner and to the same extent irrespective of its negligence.
Yes. The plaintiff need not prove that but for the railroad's fire the property would have been saved. It is sufficient that the railroad's negligently set fire was a material element and substantial factor in producing the destruction. The verdict for the plaintiff was proper.
Anderson is a cornerstone of tort causation doctrine. It supplies the substantial factor test used when multiple sufficient causes operate, and it addresses burden shifting in concurring-cause cases. The decision prevents negligent defendants from exploiting causal indeterminacy created by concurrent forces and has been influential in the Restatement approach to actual causation. For students, it illuminates the limits of but-for causation, the rationale for alternative causation tests, and the interplay between doctrinal precision and policy in allocating the risk of uncertainty.